|
Propionibacteria
''Propionibacterium'' is a Gram-positive bacteria, gram-positive, anaerobic, rod-shaped genus of bacteria named for their unique metabolism: They are able to synthesize propionic acid by using unusual transcarboxylase enzymes. Its members are primarily facultative parasites and Commensalism, commensals of humans and other animals, living in and around the sweat glands, sebaceous glands, and other areas of the skin. They are virtually ubiquitous and do not cause problems for most people, but propionibacteria have been implicated in acne and other skin conditions. One study found the ''Propionibacterium'' was the most prevalent human skin-associated genus of microorganisms. In ruminants, propionibacteria reduce nitrate to nontoxic nitrogen compounds. Members of the genus ''Propionibacterium'' are widely used in the production of vitamin B12, vitamin B12, tetrapyrrole compounds, and propionic acid, as well as in the probiotics and cheese industries. The strain ''Propionibacterium ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionibacterium Freudenreichii
''Propionibacterium freudenreichii'' is a gram-positive, Motility, non-motile bacterium that plays an important role in the creation of Emmental cheese, and to some extent, Jarlsberg cheese, Leerdammer and Maasdam cheese. Its concentration in Swiss cheese (North America), Swiss-type cheeses is higher than in any other cheese. Propionibacteria are commonly found in milk and dairy products, though they have also been extracted from soil. ''P. freudenreichii'' has a circular chromosome about 2.5 Mb long. When Emmental cheese is being produced, ''P. freudenreichii'' ferments lactate to form acetate, propionate, and carbon dioxide: (3 C3H6O3 → 2 C2H5CO2 + C2H3O2 + CO2). The products of this fermentation (food), fermentation contribute to the nutty and sweet flavors of the cheese, and the carbon dioxide byproduct is responsible for forming the holes, or "Eyes (cheese), eyes" in the cheese. Cheesemakers control the size of the holes by changing the acidity, temperature, and curing time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Bacterial Orders
This article lists the orders of the Bacteria. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI) and the phylogeny is based on 16S rRNA-based LTP release 132 by The All-Species Living Tree Project. Phylogeny National Center for Biotechnology Information (NCBI) taxonomy was initially used to decorate the genome tree via tax2tree. The 16S rRNA-based Greengenes taxonomy is used to supplement the taxonomy particularly in regions of the tree with no cultured representatives. List of Prokaryotic names with Standing in Nomenclature (LPSN) is used as the primary taxonomic authority for establishing naming priorities. Taxonomic ranks are normalised using phylorank and the taxonomy manually curated to remove polyphyletic groups. Cladogram was taken from GTDB release 09-RS220 (24 April 2024). Kingdom Bacillati Phylum Chloroflexota * Class "Bathosphaeria" Mehrshad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionic Acid
Propionic acid (, from the Greek language, Greek words πρῶτος : ''prōtos'', meaning "first", and πίων : ''píōn'', meaning "fat"; also known as propanoic acid) is a naturally occurring carboxylic acid with chemical formula . It is a liquid with a pungent and unpleasant smell somewhat resembling body odor. The anion as well as the Carboxylate salt, salts and esters of propionic acid are known as propionates or propanoates. About half of the world production of propionic acid is consumed as a preservative for both animal feed and food for human consumption. It is also useful as an intermediate in the production of other chemicals, especially polymers. History Propionic acid was first described in 1844 by Johann Gottlieb, who found it among the degradation products of sugar. Over the next few years, other chemists produced propionic acid by different means, none of them realizing they were producing the same substance. In 1847, French chemist Jean-Baptiste Dumas esta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionibacterium Acnes
''Cutibacterium acnes'' (''Propionibacterium acnes'') is the relatively slow-growing, typically aerotolerant anaerobic, gram-positive bacterium (rod) linked to the skin condition of acne; it can also cause chronic blepharitis and endophthalmitis, the latter particularly following intraocular surgery. Its genome has been sequenced and a study has shown several genes can generate enzymes for degrading skin and proteins that may be immunogenic (activating the immune system). The species is largely commensal and part of the skin flora present on most healthy adult humans' skin. It is usually just barely detectable on the skin of healthy preadolescents. It lives, among other things, primarily on fatty acids in sebum secreted by sebaceous glands in the follicles. It may also be found throughout the gastrointestinal tract. Originally identified as ''Bacillus acnes'', it was later named ''Propionibacterium acnes'' for its ability to generate propionic acid. In 2016, ''P. acnes'' w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propionibacterium Acidifaciens
''Propionibacterium acidifaciens'' is a Gram-positive, anaerobic and pleomorphic bacterium from the genus of Propionibacterium which has been isolated from a human oral cavity in London in England England is a Countries of the United Kingdom, country that is part of the United Kingdom. It is located on the island of Great Britain, of which it covers about 62%, and List of islands of England, more than 100 smaller adjacent islands. It .... References Propionibacteriales Bacteria described in 2009 {{Propionibacterineae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tetrapyrrole
Tetrapyrroles are a class of chemical compounds that contain four pyrrole or pyrrole-like rings. The pyrrole/pyrrole derivatives are linked by ( or units), in either a linear or a cyclic fashion. Pyrroles are a five-atom ring with four carbon atoms and one nitrogen atom. Tetrapyrroles are common cofactors in biochemistry and their biosynthesis and degradation feature prominently in the chemistry of life. Some tetrapyrroles form the active core of compounds with crucial biochemical roles in living systems, such as hemoglobin and chlorophyll. In these two molecules, in particular, the pyrrole macrocycle ring frames a metal atom, that forms a coordination compound with the pyrroles and plays a central role in the biochemical function of those molecules. Structure Linear tetrapyrroles (called bilanes) include: *Heme breakdown products (e.g., bilirubin, biliverdin) * Phycobilins (found in cyanobacteria) * Luciferins as found in dinoflagellates and euphausiid shrimps (krill) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Probiotics
Probiotics are live microorganisms that provide health benefits when consumed, generally by improving or restoring the microbiota in the Gut microbiota, gut. Probiotics are considered GRAS, generally safe to consume, but may cause bacteria–Host (biology), host interactions and unwanted side effects in rare cases. There is some evidence that probiotics are beneficial for some conditions, such as helping to ease some symptoms of irritable bowel syndrome (IBS). However, many claimed health benefits, such as treating eczema, or curing vaginal infections lack substantial scientific support. The first discovered probiotic was a certain strain of bacillus in Bulgarian yoghurt, called ''Lactobacillus bulgaricus''. The discovery was made in 1905 by Bulgarian physician and microbiologist Stamen Grigorov. The modern-day theory is generally attributed to Russian Nobel Prize laureate Élie Metchnikoff, who postulated around 1907 that yoghurt-consuming Bulgarian peasants lived longer. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cheesemaking
Cheesemaking (or caseiculture) is the craft of making cheese. The production of cheese, like many other food preservation processes, allows the nutritional and economic value of a food material, in this case milk, to be preserved in concentrated form. Cheesemaking allows the production of the cheese with diverse flavors and consistencies. History Cheesemaking is documented in Egyptian tomb drawings and in ancient Greek literature. Cheesemaking may have originated from nomadic herdsmen who stored milk in vessels made from sheep's and goats' stomachs. Because their stomach linings contain a mix of lactic acid, bacteria as milk contaminants and rennet, the milk would ferment and coagulate.Kats, Sandor Ellix; Pollan, Michael (2015). The Art of Fermentation an In-depth Exploration of Essential Concepts and Processes from around the World. Vermont: Chelsea Green Publishing. A product reminiscent of yogurt would have been produced, which through gentle agitation and the separation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eyes (cheese)
Eyes are the round holes that are a characteristic feature of Swiss-type cheese (e.g. Emmentaler cheese) and some Dutch-type cheeses. The eyes are formed by bubbles of carbon dioxide gas during the cheesemaking process. The gas is produced by various species of bacteria in the cheese. Swiss cheese In Swiss-type cheeses, the eyes form as a result of the activity of propionic acid bacteria (''propionibacteria''), notably ''Propionibacterium freudenreichii'' subsp. ''shermanii''.P.L.H. McSweeney, ''Biochemistry of Cheese Ripening: Introduction and Overview'', in: Fox, p. 349 These bacteria transform lactic acid into propionic acid and carbon dioxide, according to the formula: :3 lactate → 2 propionate + acetate + CO2 + H2O The CO2 so produced accumulates at weak points in the curd, where it forms the bubbles that become the cheese's eyes. Not all CO2 is so trapped: in an cheese, about 20 L of CO2 remain in the eyes, while 60 L remain dissolved in the cheese mass and 40 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acne Vulgaris
Acne ( ), also known as ''acne vulgaris'', is a long-term Cutaneous condition, skin condition that occurs when Keratinocyte, dead skin cells and Sebum, oil from the skin clog hair follicles. Typical features of the condition include comedo, blackheads or whiteheads, pimples, oily skin, and possible scarring. It primarily affects skin with a relatively high number of sebaceous gland, oil glands, including the face, upper part of the chest, and back. The resulting appearance can lead to lack of confidence, anxiety (mood), anxiety, reduced self-esteem, and, in extreme cases, clinical depression, depression or suicidal ideations, thoughts of suicide. Susceptibility to acne is primarily genetic in 80% of cases. The roles of diet and cigarette smoking in the condition are unclear, and neither hygiene, cleanliness nor exposure to sunlight are associated with acne. In both sexes, hormones called androgens appear to be part of the underlying mechanism, by causing increased production ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emmental Cheese
Emmental, Emmentaler, or Emmenthal is a yellow, medium-hard cheese that originated in the Emme Valley in Switzerland. It is classified as a Swiss-type cheese. History Emmental cheese originates from the Emme Valley in Switzerland. It has a savory but mild taste. While "Emmentaler" is registered as a geographical indication in Switzerland, a limited number of countries recognize the term as a geographical indication: similar cheeses of other origins, especially from France (as "Emmental"), the Netherlands, Bavaria, and Finland, are widely available and sold by that name. In some parts of the world, the names "Emmentaler" and " Swiss cheese" are used interchangeably for Emmental-style cheese. Production Three types of bacteria are needed to prepare Emmental: ''Streptococcus thermophilus'', '' Lactobacillus helveticus'', and ''Propionibacterium freudenreichii''. Historically, the eyes were a sign of imperfection, and until modern times, cheese makers would try to avoid them. No ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Comedones
A comedo (plural comedones) is a clogged hair follicle (pore) in the skin. Keratin (skin debris) combines with oil to block the follicle. A comedo can be open (blackhead) or closed by skin (whitehead) and occur with or without acne. The word ''comedo'' comes from Latin ''comedere'' 'to eat up' and was historically used to describe parasitic worms; in modern medical terminology, it is used to suggest the worm-like appearance of the expressed material. The chronic inflammatory condition that usually includes comedones, inflamed papules, and pustules ( pimples) is called acne. Infection causes inflammation and the development of pus. Whether a skin condition classifies as acne depends on the number of comedones and infection. Comedones should not be confused with sebaceous filaments. Comedo-type ductal carcinoma ''in situ'' (DCIS) is not related to the skin conditions discussed here. DCIS is a noninvasive form of breast cancer, but comedo-type DCIS may be more aggressive, so may b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
